This invention relates generally to flow controlling dual hydrants, and more particularly to improvements in adjustable hot and cold water hydrants.
There is need in such hydrants or dual valves for reliably blocking or checking back flow where reverse flow pressure may build up, as in a hot and cold water mixing zone. Also, there is need in such hydrants or valves for disposing of back flow pressure that may build up in the mixing zone. Such back flow, if unchecked, could contaminate up-stream liquid such as water, in plumbing, and in particular cold water plumbing. Further, there is need for simplification of such hot and cold water hydrants, where the use of two check valves to check both hot and cold water flow is too costly.